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Background: The ACTN3 R577X polymorphism has been associated with an elite athlete status. Several studies have determined that the R allele is connected with power-oriented athletic performance, whereas the nonfunctional XX genotype may give some beneficial effect for endurance performance. The main aim of the study was to determine the possible interaction between the ACTN3 R577X polymorphism and an endurance athlete status in a group of Polish rowers in comparison with sedentary individuals. Material/Methods: 121 male Polish rowers, members of academic sports clubs, and 115 unrelated volunteers were recruited for the study. Genotyping for the R577X variant was performed by PCR–RFLP. Results: The genotype distribution amongst the rowers (52.06% RR, 38.85% RX, 9.09% XX) was significantly different from that amongst sedentary individuals (RR-33.5%; RX- 49.60%; XX-17,35%; P = 0.024). A significant excess of the R allele was noted in the rowers (71.48%, P = 0.008) when comparing with the controls (60.0%). Conclusions: The obtained results show that the ACTN3 X allele and XX genotype are underrepresented in Polish rowers and they are not advantageous for the endurance-type athletes in the studied population. On the contrary, the R allele seems to be useful for a top-level rower. However, additional studies are needed to clarify this problem.
Background: The aim of the study was to designate changes in the expression of HSPA1A, HSPB1 and LDHb in elite rowers after completing a test “till exhaustion” on a rowing ergometer. Finally, we searched for the answer whether there are significant correlations between the expression of the genes and anaerobic threshold (AnT) or the maximal oxygen uptake (VO2max). Material/Methods: The research was conducted on the sample of 9 Polish lightweight male rowers (23.7 ±3.77 yrs, 72.7 ±1.76 kg, 183.6 ±4.58 cm). To determine AnT and VO2max, the subjects performed the test “till exhaustion” with an increasing load on a rowing ergometer. Directly before and after the test, blood samples were collected from the ulnar vein in order to isolate genetic material. RNA was extracted from white cells of venous blood by the chemical method. 2 µg RNA for the reverse transcription was used and the expression of HSPA1A, HSPB1 and LDHb was determined by Real time PCR reaction. To assess the intensity of expression, the ∆∆Ct method was used. Results: The study showed an increased expression of HSPA1A and HSPB1 and a decreased one of LDHb. Moreover, post-training changes of the genes activity in white blood cells occurred immediately and could be determined directly after the termination of exertion. Conclusions: No significant correlations between the expression of the genes and anaerobic threshold (AnT), maximal oxygen uptake (VO2max) were stated.
Background: The present study was performed to clarify fatigue-induced effects of a strenuous and moderate intensity endurance training session on temporary changes of cardiopulmonary (CP) chemosensitivity and fast kinetics response. Material/Methods: Eleven high performance (national level) male rowers participated in this study [age 21.8 ±1.7 (range 18-25 years), 89.3 ±2.0 kg, 190.1 ±1.7 cm, VO2 max 67.9 ±1.1 ml·kg-1·min-1]. The studies involved three steps: 1) a study of effects related to a training session of moderate intensity, 2) effects of a high intensity session, and 3) an impact of a high intensity session on values of peak response. The high intensity session consisted of intermittent training loads made up of five sets of four repetitions of sixty-second work intervals (HR of 149-186 bt·min-1). The moderate intensity session consisted of unvarying type of exercise (HR of 138-167 bt·min-1). Measurements were made at rest before, 13-15, and 37-39 hours after the training session. In rebreathing tests ventilatory sensitivity to CO2 and HR response sensitivity to normocapnic hypoxia were measured. Fast kinetics of ventilation, oxygen uptake, CO2 production and the heart rate were measured in a 5-min standard power test (0.7 VO2 max, 5 min, transition from 25 w) and in a 6-min test (1.12 ±0.11 VO2max). Results: We found that a training session of high intensity resulted in a significant decrease in sensitivity to hypercapnia, an increase in CP sensitivity to hypoxia, a decrease in CP fast kinetics and stability of peak response 13-15 hours after the session vs. baseline. Mean power in a 6-min maximum test decreased, which was mainly determined by a decrease in mean power during the first 3 min and utilization of VO2 max for a 6-min test. Moderate intensity of a training session resulted in an increase in ventilatory sensitivity to hypercapnia whereas sensitivity CP to hypoxia and fast kinetics remained unaffected. Conclusions: These results suggest that not only CP chemosensitivity to hypoxia but also CP chemosensitivity to hypercapnia are variable in high intensity endurance training. The variability related to the effect of fatigue in the recovery phase (up to 15-15 hours) after strenuous training sessions.
Angiotensin converting enzyme gene (ACE) is the most frequently investigated genetic marker in the context of genetic conditioning of athletic predispositions. The product of the gene is a key component of the renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS), mainly responsible for the regulation of blood pressure. The main aim of the study was to determine the possible interaction between the ACE l/D polymorphism and endurance athlete status in a group of Polish rowers in comparison with sedentary individuals. 121 male Polish rowers, members of academic sports clubs, and 115 unrelated volunteers, were recruited for the study. The PCR amplification of the insertion (I) or deletion (D) fragment of the ACEgene was performed. Compared with control group, the frequency of the I allele differ significantly from that found in rowers (57.4% vs. 44.3%; P = 0.013) and the ACE genotype frequency amongst the whole cohort of rowers (30.6% II, 53.7% ID, 15.7% DD) was also different from expected values (control group 19.1% II, 50.4% ID, 30.4% DD; P=0.017). Our investigation confirms a positive association of the I allele of the ACE gene with endurance athlete status in a group of Polish rowers.
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